1. Field of the Invention
The present invention relates to a doorframe assembly for a door opening in hollow wall partition construction, and more particularly refers to such a structure which facilitates setting the door jambs to the exact dimensions of the header, thereby eliminating any manufacturing tolerances.
2. Description of the Prior Art
Hollow partition wall construction featuring quick installation and field adaptability to particular construction requirements has become very desirable in recent years. Together with the hollow wall construction, framing for door openings must also allow for ease of installation with members that can be interchangeably used as particular needs arise in an overall office, residence, or factory partition wall system. It has become particularly important to provide framing members which can be interchangeably used and individually altered in the field.
Many prior art door frame techniques utilize extruded metal and vinyl elements to provide required quick installation. Typically, an exposed extruded jamb member provides slotting or notching for hinge members, securing plate members, door stops, trim plates, strike plates, and an array of necessary hardware elements for door framing. Unfortunately, many prior systems restrict attachment of hinge plates to only one jamb member and a strike plate to an opposing jamb member at the other side of the door opening. Also, some systems have large assortments of accessory parts that involve lengthy installation operations for their attachment. It would be desirable to provide door framing members which allow reversibility of jamb members with a limited number of accessory parts that would expedite installation and allow interchangeability of members having equally adaptable use at various door openings without limitation to a specific door opening location in a hollow wall partition construction.
It has also become a need of the construction industry to provide a door jamb member which permits the variable location of hinge plates without limitation to specifically notched portions. In attempting to solve this problem, past attempts have typically been limited to connection of hinge plates with metal members. With increased costs of providing decorative exposed metal jamb members the use of extruded vinyls has been explored. Problems, however, have arisen when trying to incorporate extruded vinyl members or thin wall aluminum members in that attachment to door opening sides necessitates the use of a sturdy metal backer of some sort. Complex shapes for metal backer jambs have thus been required in order to permit versatile location of hinge plate means. The hinge plate is then attached and followed by attachment of numerous extruded trim elements concealing unsightly and undecorated metal backer jambs. In many attempted solutions, a difficulty has arisen in providing the necessary thickness of metal backer members that feature surfaces usable with screw fasteners for affixation of hinge plate means to afford necessary strength for door support. Although hollow-core doors may be used to reduce weight and thus alleviate the requirement of extra strength, it would be highly desirable to have adaptability for use with a hollow-core or solid-core door in a hollow wall partition construction where needed. Conventional solid-core doors may range up to about 150 lbs. and sufficient strength of screw fastener attachment at hinge plate means is mandated. Efforts to provide this have been made wherein additional metal plates, shims, or plate means are inserted along a metal backer jamb behind hinge plate means to provide the necessary thicknesses for the conventional screw fastener attachment of hinge plate means involving the use of a heavier door.
At the side of a typical door opening where strike plate means coact with door locking means, a similar problem for allowing variable location of the strike plate has been confronted. In many recent attempts, the jamb at the strike side of the door opening requires a different shape and manner of installation than the jamb at the hinge side of the door opening. Moreover, pre-cut notches for attachment of a strike plate means necessarily limits the ability to provide universal support structures to be used at various door locations having different strike plate height requirements. In previous solutions to reversible jamb member framing, there has typically been provided a complex jamb member which allows for use at either side of the door opening, but requires additional material for extruding, or roll forming, cover plate members and engageable slots on jamb members to attain this feature.
In U.S. Pat. Nos. 4,223,494 and 4,281,480, by the present inventor, there are disclosed various improvements in the construction of doorframes. However, in regard to all the doors of the prior art it has been difficult to provide a structure wherein perfectly mitered header joints could be more readily obtained.